Saturday 26 December 2009

Electrolux Update

Long time no post.

After traveling around the world in November for work, Christmas has now been and gone.

4 weeks ago I found the tops of the contactors (relays) that connect the 48 volt battery blocks together were loose. Since then the electrolux has run almost perfectly. I am not sure a bouncing contactor could cause the "Earth Fault" but this is the only thing I have found wrong.

the pre-charge contactor in the VFD is sometimes not closing properly, but that causes an under voltage alert.

So all in all things are going well. Fingers crossed.

I have now traveled over 1100 km and am wearing the EV grin as I see the petrol prices steadily increasing.

Monday 16 November 2009

I'm go'in on a bear hunt... and Friday the 13th.

I have been traveling for work this month and am currently in the US, in NJ. I took a Sunday drive today to the High Point State Park and the Delaware Water Gap. When I was driving through some beautiful autumnal bush I saw a guy stopped taking photos of a bear. Never having seen a bear in the wild, I had to stop and take a pic.

Also, I stopped for a snack at Blairstown Diner. Its claim to fame is that it was one of the locations for Friday the 13th. Here is a shot of the Diner and the 'Canyonero'

Wednesday 21 October 2009

Blue Toung Lizard

This Blue tongue wandered past my office door today. Its nice to see some wildlife around.

Ive got some good news and some bad news

Bad news first. The ute is dieing with the 'Earth Fault' on the controller pretty much daily this week. After running faultlessly for over a week.

The good news is that I may be isolating the problem to a connector in the drive.

Time will tell.

Sunday 18 October 2009

A New Look At An Old Design The Prehistoric Alignment Of World Wonders

This is fascinating reading! at least for those that enjoy geography, math & history.

Ancient civilizations were way smarter than we give them credit for!

I wonder how this fits with biblical timelines and history. Presumably post Noah (2400BC) / Tower of Babel (2300BC)

"Great circles are straight lines that go all the way around the center of the earth. The equator is a great circle. Meridians of longitude that cross over the north and south poles are also great circles. For every location on a great circle, it's antipodal location is also on the circle. Other than the equator itself, any great circle crosses the equator at two antipodal locations, 180° apart. Other than the equator and meridians of longitude that run due north and south, any great circle reaches it's maximum latitudes at two locations that are 90° of longitude east and west of the two locations where the great circle crosses the equator.

Easter Island, Nazca, Ollantaytambo, Paratoari, Tassili n'Ajjer and Giza are all aligned on a single great circle. Additional ancient sites that are located within one tenth of one degree of this great circle include Petra; Perseopolis; Khajuraho; Pyay, Sukothai and Anatom Island.

Near Ollantaytambo, Machupicchu and Cuzco are within one quarter of a degree. The Oracle at Siwa in the western Egyptian desert is within one quarter of a degree. In the Indus Valley, Mohenjo Daro and Ganweriwala are within one quarter of a degree. The ancient Sumerian city of Ur and Angkor temples in Cambodia and Thailand are within one degree of the great circle. The Angkor temple at Preah Vihear is within one quarter of a degree."

The Improbable Research Awards

Research that makes people LAUGH and then THINK

Ig Nobel Prize

Tesla ride

Here is a pic of me in the Tesla Roadster a couple of weeks ago.

0-100km/hr in 3.8s :)

Orange cable bad / Clear cable good.

I swapped the motor cable in my ute last weekend on the advice of a few people with a lot of experience dealing with variable frequency drives. The ute has been running for a week trouble free so I am hoping that the new cable has solved the intermittent "Earth Fault" error that was happening.

I originally wanted this kind of cable but was unable to locate any at the wholesalers. I found what I needed only after asking to look through their supplier catalogs.

The cable is distributed by Bambach Wires & Cables. From TLE the part number is BAM45903CRS in case anyone is looking for some. The construction is 3 x 10mm^2 3 phase, with 3 earths ~2mm^2 and a foil and braided shield.

Make sure the cable is terminated correctly at the motor using a metal gland that contacts the braid and as per the VFD manufacturer's instructions at the drive.

As the fault was very intermittent, I will be satisfied this has solved the problem if I don't experience this problem for another 2 weeks.

Here is a photo of the cable.

Wednesday 23 September 2009

Back to square one

After installing a spare current sense board in the ute's speed controller, it tripped with an earth fault again on Sunday.

Might have to get hold of another motor for testing.

Walking to work does me good, except when there is a massive dust storm over Sydney!

Friday 11 September 2009

Hopefully the ute is fixed

The speed controller has been stopping with an "earth fault" intermittently with increasing regularity.

After talking to the Danfoss service guy, thanks Gavin, I installed a similar current sense board as this is where the problem seemed to be. The ute ran fine for about a week.

Last week I took the original board and soldered in a resistor array that was in a socket and re soldered the current sensors then replaced the board into the ute.

I have been driving for about 5 days, so far without fault. Lets hope that is the end of the problems!

Wednesday 9 September 2009

How to use a Blackberry without a Blackberry service

This allows you to use the normal data service without subscribing to the often expensive blackberry services (BES/BIS) offered by telcos.

If you load google sync, gMail, gMaps etc it woulks perfectly for personal use.

This Servcei book entry creates a CMIME and BrowserConfig service book entry that uses the data channel instead of BES.

Birds on a Wire

Very clever

Excelent new way of creating PCBs at home

You can use this holder in certain Epson inkjet printers to print the etch resist onto PCBs.

I have ordered a kit and will post the results.

Now to find a suitable printer...

Friday 28 August 2009

Fail again

The VFD tripped again yesterday when I went to drive it.

Today i swapped the current sense board from the spare VLT6042 to the VLT5042. The PCBs are similar enough but the current reads about 2x as high. The current sensors must be different in each board. Damn. I am awaiting a call from Danfoss to see if the drive has a different setting for different current sensors. Its a long shot I know.

There was a resistor array on the VLT5042 current sens board that was in a socket. I have soldered it in in case it was loose.

Tuesday 25 August 2009

So far so good

After resetting the Danfoss speed controller today, the ute hasn't missed a beat.

Time will tell weather the fix is permanent. I certainly hope so!

The Electrolux might just be fixed.

I gave the Danfoss service guy a call this morning about my earth leakage trip problem. He suggested the following.

  1. Copy the program to the LCP (Menu 7 - upload)
  2. Reset the controller using a key sequence only a contortionist can perform
  3. Copy the program back to the controller from the LCP
  4. Give it a go.
Well I connected up the motor as I had previously done an earth leakage test on it (it passed)
I turned the ute on held the brake down and pressed the throttle. Sure enough it predictably tripped.
Then I performed the sequence above, and retested up to max current with my foot on the brake.

So far so good. Lets hope this sorts it out. Apparently the hall effect current sensors can build up an offset giving a false current trip. Resetting the controller forces the system to recalibrate using the offset.

The service tech mentioned for this fault to occur requires about a 20% current imbalance between phases which is more significant than I had thought.

Why didn't I call him 2 weeks ago???

Fingers and toes will be crossed on my drive to work today!

I will update in a few days the outcome.

Too many hobbies - Arcade Machine

A friend of mine ('Striker') recently offered me cocktail arcade machine without a game board inside in exchange for fixing another cocktail cabinet machine. This is something I have wanted for years and never got around to building. The complete cabinet was a Godsend.

After a steep learning curve and a trip with the screen to the local tv repair guy, thanks Horst, I was able to get Striker's machine going and then bought the parts for mine.

The cabinet is a Taito of about 1982 vintage. It has 2 player positions and an original 20" monitor that can be rotated to horizontal or vertical depending on the game board.

I had to pick the 2 round locks (like laptop cable locks) to open the lid and the coin bin lock. This was actually quite fun. It was surprisingly easy after watching a few YouTube videos on the subject. I found the grand sum of $2 in twenty cent pieces.

After a lot of inspection, googling for schematics and some advice from the Aussiearcade forums I started the rejuvenation, including removing old chewing gum.

I cleaned up the mains power supply and removed the redundant wiring.
I removed the switch mode supply as it was faulty.

I installed a new power supply, new cable harness and the best part of all 60 in one game board.
The connector on the original cable harness was quite unusual and could not be reused.

I now have 60 classic games to play. I love it, the kids love it, even my wife likes to play it.
The favorite at the moment is Pinball.

Each player position only had one 'fire' button so I moved both buttons to one side, and added 2 new buttons to the other. The new buttons work fine but don't fit quite right. I would like to keep the exterior original so I am looking for some 2 original and quite rare Taito buttons the same as this one pictured.

Helicopter Flight and ILLW

The weekend before last was International Lighthouse and Lightship weekend. This is where many lighthouses around the world are opened to the public in commemoration of the often lonely and dangerous work the lighthouse keepers used to do.

The Amateur radio club I belong to, the MWRS, set up a station at Barrenjoey lighthouse on the Saturday and Sunday.

I was fortunate enough to be invited by Yves and his partner Connie, fellow MWRS memebers, to go for a flight the in Bell 47 he flies. We went from Bankstown airport to Parramatta, followed the Hawkesbury to Barrenjoey lighthouse. We circled the lighthouse twice and returned to Bankstown via the northern beaches, The Opera House and the Harbour bridge. The weather could not have been better, and the views were nothing short of spectacular. The rough route can be followed by APRS

For those not in Australia, I recommend you take the time to look at the photos.
I have uploaded the photos to my flickr account.


Unfortunatly my electic ute (pickup) has had some problems. The VFD is tripping with an earth leakage fault. The problem has been intermitent and usually restarts, but this time it let me down and I needed a tow home. I have been testing a few thigns, and short if getting a new motor there is not much I can do. The good news is a new motor is only about $400. This will also give me the oportunity to rewind the old motor for higher top speed. Something along the lines of this post.

Friday 24 July 2009

Frequently Asked Questions for EV upgrades. FAQ.

I often get asked questions about EV conversions so I thought I would gather many of the answers. below.

Electric Vehicle Upgrades: FAQ.

What kind of car should I get upgraded?

Essentially any car can be upgraded however some lend themselves to a simpler, easier and cheaper conversion than others. Here are some rules of thumb to follow:

  • Look for a vehicle that is pre 2002 as the integration of the electronics tends to be simpler. Once the petrol motor is removed, the engine management computer will complain and this may affect other computers in the vehicle such as the Dashboard, Security and Air Conditioning ECUs in many modern vehicles.
  • Upgrade a vehicle that you would like driving. You should hope to get many years of good service from the vehicle.
  • Find a vehicle with no rust, panel damage and a good interior. You don’t want to have to spend thousands of dollars on panel and paintwork
  • The vehicle weight and load carrying capacity must be considered. A vehicle that weighs less than 1100kg and have a GVM (Gross Vehicle Mass/ maximum loaded weigh) of 1400kg or more. The difference between these weights will determine how many and how large the batteries can be and also the number of passengers. 85kg per passenger must be included when calculating GVM.
  • For a DC motor upgrade the vehicle must have a manual transmission.
  • For a slightly more expensive AC motor upgrade you should choose an automatic only if the motor comes with suitable reduction gearbox and differential.
  • A front wheel drive vehicle often has more possibilities for the battery location in that they may be installed under the rear set due to the lack of a driveshaft beneath the vehicle. In a rear wheel drive vehicle, the battery pack will invariably need to be split over 2 or more locations including luggage space.

How far can I go?

The answer is that it depends, but I will give a typical example.

  • A car typical small car weighing 1100kg with a 144V, 100Ah battery pack will have a range of about 80km to 80% discharged
  • The same small car using 160Ah batteries will have a range of about 120km. These would be the largest practical batteries you could use.
  • If the vehicle is heavier, terrain is very hilly, or you are travelling at high speed, the range will be less.
  • The effect on range of heating and air conditioning will be 5-15% depending on use.
  • The number of passengers or load will have a small effect on range. In stop start traffic this will be between 5-15%.
  • The larger the vehicle, the less range it will have. A 1600 kg vehicle with a 144v, 100Ah lead acid battery pack will have a usable range of 35km.
  • A 2000kg vehicle with 144V 200Ah Lithium battery pack will have a range of about 50km.

How Fast can I go?

· Upgraded vehicles are usually capable of freeway speeds of 110km/hr.

· Some upgraded commercial vehicles may be limited to 90 – 110 km/hr for city use, giving increased range.

Battery life cycle.

· Lithium batteries have a cycle life of 3000 cycles if not discharged below 80% capacity. This is about 11 years if the vehicle is driven 5 days a week. The capacity is viewed on a specially designed battery ‘fuel’ gauge. More advanced gauges may also show a distance to empty. If the battery is discharged below 80% capacity frequently the cycle life can be as low as 1500 cycles.

· Good Lead acid batteries that are designed for electric vehicles have a cycle life of about 400 cycles to 80% discharged or 800 cycles to 50% discharged. 800 cycles equates to about 3 years.

How long will it take to charge my batteries?

· A typical 144v, 100Ah battery pack will take 6 hours from fully discharged when charged from a typical 10A power point. Realistically the duration will be less as the batteries will never be fully discharged.

· We also have fast chargers available that can charge the 100Ah pack in 3 to 4 hours.

· Larger 160Ah batteries will take proportionally longer to charge 8-10 hours using a standard 10A power point.

How heavy are the batteries?

· A 144v 100Ah lithium battery pack will weigh 144kg

· A 144v 160Ah Lithium battery pack will weigh 252kg

· A 100Ah Lead Acid battery pack will weigh 340kg for a 120v system or 413kg for 144v.

· The additional weight of the batteries is largely overcome by the removal of the fuel tank, exhaust, radiator and the petrol engine.

· In some vehicles, especially older models, the suspension springs may need replacing to retain original ride height.

How safe is an upgraded vehicle?

There is significant effort put into the safety Eve Motor Group upgraded electric vehicles. Following are some of safety features.

· The vehicle fully complies with the Road Transport Authorities National Code Of practice # 14 for electric vehicle conversion.

· The vehicle complies will all Blue Slip (NSW) requirements

· A crash sensor in installed that will disconnect the motor in case of an accident

· Fuses between all battery banks and a circuit breaker is installed in case of a controller or high current cable fault.

· All battery compartments, battery restraints and component anchor points are designed to comply with the G force requirements in case of crash and roll over.

How much will it cost to charge?

The charging cost primarily depends on how far you have driven. Let’s work it out.

· Say our car averages 180Wh/km. We drive 50km so we use 9kWh of electricity.
Battery chargers are about 85% efficient so this means that we might use 11.25kWh to charge.

· In a residential, Using power at normal retail rates(say 20c/kWh) this might cost $2.25, or 4.5c/km

· Residential off peak rates during 10pm to 6am (.6c/kWh) might cost 1.35c per km

· Large business pay as little as 7c peak and 4c off peak

· You can buy plug in a power meter from Jacar Electronics Part number MS6115 for about $40 that will calculate your charging costs. Alternatively for about $100 a kWh meter can be installed in the vehicle.

How do I charge using cheaper off peak power?

· If you have an older meter box, ask your electrician to install an off peak power point in your parking space. This will only be powered between 10pm and 6am (longer on weekends) and charged through a separate meter at off peak rates.

· If you have a newer smart meter, you can add a timer available from electrical suppliers on the power point you use for charging and set it to only turn on when lower priced electricity is available.

Should I keep the clutch?

· In my opinion, Yes. Many mechanically minded people will boast they can drive a car with a manual gearbox without a clutch, and in fact driving an EV without a clutch is not difficult. However, everyone that drives your vehicle in the future will be used to it, so it is best to leave it in so that anyone familiar with driving a manual can drive the EV.
It is important to remember that it might be possible (depending on the speed controller) to over rev the motor and shorten its life, or worse, destroy it. This can be overcome by the use of a rev limiter most modern speed controllers. All Eve Motor Group controllers have a rev limiter built in.

· One concern of keeping the clutch is that the bearings in the motor are not designed for axial load, however according to the motor manufacture; the bearings are able to take the axial load created by the clutch plate and springs.

Can I tow a trailer?

· Towing a trailer with an electric vehicle is possible for short distances but is not recommended due to the additional load on the batteries.

Where is the nearest upgrade centre?

· Our conversion centre is located in north-west Sydney; however we are planning to open other upgrade centres around Australia.

How much does it cost?

· Please contact the Eve Motor Group via the online form to proceed with an estimate based on your requirements.

Saturday 27 June 2009

More ev posts

For those following my EV, there has been a lack of posts recently.
There are a few reasons.
1. I am happily driving my electric hilux (electro-lux) and have now done over 1100km.
2. I have been catching up on some home maintenance. I just finished a retaining wall.
3. Here is a sneak peek at something I have been working on in my spare time. More details to follow.

Camera on a sushi conveyer

Camera on sushi conveyer

Tuesday 16 June 2009

I got given this very nice book on motor repair and rewinding.

It includes an extensive chapter on 3 phase AC. The copyright is 1946, and not much has changed since then.
The AC nuts on the AEVA forums might kill for this.

Tuesday 9 June 2009

How Much does it cost to charge?

Not much compared to the same period last year (may).

Note the cost per day is total household usage.

Friday 5 June 2009


"All mankind is divided into three classes: those who are immovable, those who are movable; and those who move."
-Benjamin Franklin

Monday 25 May 2009

EV Links

Thanks for visiting my blog.

The best way to read it is go to the earliest post and read from there in chronological order.

For those that have come here as a result of the SC article, here are some more links for further reading.

And if you are still keen, I have a Danfoss inverter for sale.

Article about my ute in the June Silicon Chip magazine

A month or so ago I dropped down to the SC office in Brookvale to show off, as I had previously been in touch with Leo the editor.

He decided to do a 6 page article to the Electro-Lux and I even got my picture on the cover.

Friday 8 May 2009

25 Microchips That Shook the World

This is a fun read, and nostalgic for those that have been breathing hot solder for more than 25 years.

From the IEEE

Saturday 2 May 2009

Whats the BS on

Playing for change

Here are some brilliant street performances.

On top of that the audio and video production is outstanding.

The Inspiration

Playing for Change is a multimedia movement created to inspire, connect, and bring peace to the world through music. The idea for this project arose from a common belief that music has the power to break down boundaries and overcome distances between people. No matter whether people come from different geographic, political, economic, spiritual or ideological backgrounds, music has the universal power to transcend and unite us as one human race. And with this truth firmly fixed in our minds, we set out to share it with the world

Monday 27 April 2009

A long trip to Homebush and back.

On Sunday I attended an event at Energy Australia

The trip there was  31.8km and the economy was 226Wh/km. 
The recharge time was 4 hours. (I have never had a chance to 'watch' the chargers before.)

The return trip was 39.4km (Thanks to Kearon getting lost and me making the mistake of following him) I averaged 210Wh/km. 

The extra kms were on flat ground around Olympic park. This really shows how much hills kill the batteries. I usually get abut 250Wh/km around the hilly area where I live.

My Hilux

Mark's Lotus 7 replica

Kearon's Capri

Peter's Combo

Nathan's Hyundai Excel

Electric Vehicle conversion in one week

By our AEVA 'cousins' in South Australia

Happy Birthday Sam. (Samuel Morse)

My other hobby is Amateur Radio

Saturday 25 April 2009 aims to perform the fastest, most complete distributor search available today on the internet. After you enter a part number (or substring), will simultaneously query over 20 distributors, and return the responses to you in real time, in the order completed.

Electronics Engineering video blog

By the guy that brought us the home made programmable uWatch

Thursday 23 April 2009

For anyone using twitter, this add-in rocks

This is for Firefox. It make twitter a whole lot easier to manage from the browser!

How Detroit's Automakers Went from Kings of the Road to Roadkill

Joseph B. White
Senior Editor, The Wall Street Journal

How Detroit's Automakers Went from Kings of the Road to Roadkill


I traveled 33.3km last night and averaged 249kWh/km. This is based on voltage measurement. This means to 80% discharge I can travel 38.5km.


"As for c, that is the speed of light in vacuum, and if you ask why c, the answer is that it is the initial letter of celeritas, the Latin word meaning speed." 
Isaac Asimov in "C for Celeritas (1959)"

Friday 17 April 2009

More accurate Dyno Figures

After watching the video below I noticed the power and torque were much higher. This was before the tech changed some setting on the Dyno.
I extracted a plot from the shot of the TV screen and came up with the following.

We can see that the Road torque max is 5000N which equates to a shaft torque of 315 Nm.
I think the drive is cutting back torque after the peak at 20km/hr. The nominal peak at 28km/hr is a shaft torque of 283Nm.

As for RPM, The 28km/hr equates to 1178 RPM on the motor shaft.

The big dip is still evident, a little slower at about 52km/hr.

Sunday 12 April 2009

Scatter plot of RPM vs. Torque, Power

(Power is 10x.) The above data was captured from the Danfoss VFD.
This would indicate that the Dyno run yesterday did not reach peak power / torque.50km/hr = 2100 RPM. The motor torque from the dyno plot at 50km/hr would be 2100*.323/5.125=132Nm. This (very roughly) corresponds to the scatter plot at that RPM.
The dyno plot can be for all intents ignored unfortunately. I will go and see them and see if they can do plots at multiple single speeds.

2 of my favorite things - Tesla Coils and Doctor Who!

Tesla Coils and Doctor Who! I saw these guys minus the conductior at the Maker Faire in Austin, TX last October. The performing coils have to be seen and heard to be beleived!

Saturday 11 April 2009

Dyno run - Curves

I took the Electro-Lux to a local Dyno Day today at Envy Imports. The revheds enjoyed seeing something different. I think I get the record for the lowest power and first ever EV on the Dyno.

My diff ratio is 5.125:1 and my wheel radius is about .323m.

***The dyno plot can be for all intents ignored unfortunately (see later post). I will go and see them and see if they can do plots at multiple single speeds.

Friday 3 April 2009

400km so far and no major troubles.

Today the speedo rolled over 400 electric kilometers.

There have been no significant problems, just some minor niggles.

I am confident that as long as the batteries live up to expectation I will get many 1000's of EV kilometers.

Minor changes include:
  • Replacing one battery due to a loose terminal.
  • Replacing 2 x Zener balance circuits due to mismatch.
  • Adding a series resistor to the 7 solenoids because they were getting too hot.
  • Adding an electric fan to the motor to cool it down after long up hill stretches.

Selling my hilux engine and power steering.

I am finally cleaning up the car port (Yes car port, I did the hilux conversion in a carport, I dont have a shed).

The old 22R engine and and power steering are listed on eBay

Hacked road sign

I have been sorting out some old photos and videos from my camera. This is an old video from December 2007.

1337 H4X0R3D (elite hacksawed/hacked)

Monday 23 March 2009

Danfoss VFD Switching Frequency

I tried variable switching frequency (Parameter 412) this morning but it works the opposite to what I was hoping. It does sound cool though!

It increases frequency with RPM as per the manual. I wanted a low frequency at low RPM.

Low switching frequency (Parameter 411) seems to be the key to prevent lurching and brief rear wheel lock up when decelerating to a stop. I could also try raising the stop frequency (Parameter 123) but I didnt like this set higher than 0.

Zener - Resistor battery balance circuits

I have had to make a few more Zener- resistor balance circuits as some were not evenly matched and caused 2 batteries to discharge below 13.2 at rest. They should be 13.6v (2x6.8V)

The Zener diode voltages would seem to be too low. I need to fix my adjustable PSU and measure the reverse knee voltage on them to verify the voltage and match them in sets of 4 for charging.

Friday 20 March 2009

Worlds first, registered totally industrial EV conversion

I began this planing this project after visiting the AEVA field day in October 2007. After much planing and calculating in Excel, I started purchasing parts (the motor) in December 2007. 

It took a while to find a vehicle that would suit. I looked at Toyota Town Aces, Suzuki Carrys Toyota SBVs and finally settled on a Toyota Hilux extra cab ute in April 2008. My requirements were to carry 360kg of SLA batteries + inverter and have 4 seats (for kids) without significant chassis modification. 

It was cheap for the model, but reasonably tidy. Some rust that needed dealing to but OK. This model is popular with young guys and this one had been painted black and had dark tinting, so I had to de-bogan it as well. 

To get to the point, 
I finally got it registered on the 7th of March. 

I am very happy with its performance on road. Thanks to Tuarn (acmotor on the
AEVA formus) for your inspiration in leading the way, despite me bing first to register.  

The tweaking and fiddling with settings took a while but got there in the end. It even has regeneration which is necessary in my hilly area. 

If there are any other registered industrial AC conversions around, do challenge my "subject" as I would be interested to know more about theirs, and concede to a lesser accolade of Australia or NSW.    

Thursday 19 March 2009

Mental Note, Check the battery terminals!

It would seem that I did not have one of the battery terminals tight enough.
The battery still tests OK, but I have replaced it and the balance circuit with some spares.

Thursday 12 March 2009

30km drive in Electro-Lux

I took a 34km drive last night. According to the volt meter, that equates to a final SoC of 32%. Not quite as efficient as I had hoped but there were some long hills. This amounts to 241Wh / km.

Improved Motor Cooling

The motor was getting a bit toasty after long uphill drives.

During operation the motor was cool enough but as soon as there was no air movement, the heat had nowhere to go.

I removed the shaft fan and replaced it with a 10 inch 'ICE' brand electric fan. 

The fan was attached to an aluminum plate to prevent air escaping around the fan. Coincidentally the fan mounting holes almost line up with the 4 bolt holes. I 'moved' the holes in the plastic fan by about 5mm and it looks like it was made to fit!

There is a 50 deg C 'clickson' NO thermal switch that drives a relay, that in turn drives the fan direct from the battery. This way the fan can run if necessary even if the key is off when most needed.

Air flow around the motor is very will designed. The air is blown toward the rear of the motor length ways down the cooling fins and the air exits at the rear of the motor.

i have also removed the air dam from the radiator opening to allow improved cooling.

The motor is noticeably quieter  which is a nice touch.

Here are some photos of the installation.

Old Shaft Fan

New electric fan

Temperature Switch.

Latest Danfoss VFD Parameters

By request here are my latest parameters that are changed from default...  
ID Name Setup 1 Unit (Notes)
009 Display line 2 Output energy [kWh] 
010 Display line 1.1 Dc link voltage [V] 
011 Display line 1.2 Reference [%] 
012 Display line 1.3 Torque [%] 
014 Local stop Disable 
102 Motor power 15.00 kW 
103 Motor voltage 415 V 
105 Motor current 28.00 A 
106 Motor nom. speed 1450 RPM 
108 Stator resist 0.2722 Ohm 
109 Stator react. 20.47 Ohm 
113 Lo spd load comp 150 % (For hill starts) 
114 Hi spd load comp 100 % 
115 Slip compensat. -300 % (Gives better throttle response at high speed) 
119 High start torq. 0.5 s 
128 Mot.therm protec Etr warning1 
129 Motor extern fan Yes
200 Out freq rng/rot 132 hz both direct. 
202 Out freq hi lim 132.0 Hz 
205 Max. reference 132.000 
206 Ramp type S2 
207 Ramp up time 1 6.00 s (Economy) 
208 Ramp down time 1 1.00 s 
209 Ramp up time 2 2.00 s (Power) 
210 Ramp down time 2 1.00 s 
221 Torq limit motor 348.5 % 
222 Torq limit gener 60.0 % 
224 Warn. current hi 97.6 A 
227 Warn. feedb. low -4,200.000 
228 Warn. feedb high 4,200.000 
300 Digital input 16 No operation 
301 Digital input 17 No operation 
302 Digital input 18 Latched start 
305 Digital input 29 Ramp 2 
306 Digital input 32 No operation 
307 Digital input 33 Encoder fb, input a 
314 Ai [mA] 60 funct No operation 
319 Ao 42 function Fb min-max =0-32000p (Speedo) 
320 Ao 42 puls scale 66 Hz 
321 Ao 45 function 0-tlim = 0-32000p (Tacho) 
322 Ao 45 puls scale 99 Hz 
323 Relay 1-3 funct. No operation 
326 Relay 4-5 funct. No operation 
329 Encoder pulses 40 (Inductive pickup gear) 
405 Reset mode Automatic x 2 
410 Inv.fault delay 35 s 
411 Switch frequency 3.0 kHz 
415 Max. feedback 4,500.000 
416 Ref/feedb. unit Rpm 
417 Speed prop gain 0.015 
445 Flying start Enable 
446 Switch pattern 60° avm 
457 Mains imbalance Warning

Monday 9 March 2009

Motor heat

As I live in a very hilly area, the motor is heating up a lot.
I will use Tuarns example and add a 12v cooling fan to the motor.

I am looking at a 10" radiator fan adapted to replace the existing mechanical fan. 

I will use a 'clickson' switch to allow the fan to continue running when the vehicle is off.

First decent drive observations

First of all. What fun!

Now for some stats.

24.6km Hilly terrain
Start voltage was 657v. 100%SoC according to the greensaver battery data sheet.
End voltage was 621v. 50%SoC.
Energy used (probably) = 6kwh. Efficiency = 250Wh/km

I am mixing measurements here however, the kwh counter read 8.2kwh. This is motor energy both driven and regen. This gives 2.2kWh regen which I find very hard to believe, considering the charge efficiency will not be great.

For now I will rely on the pack voltage for SoC while stationary. I have printed out a lookup table to translate voltage into SoC.

I had the regen set for 10kW (66.6%). This gave over voltage warnings (801+ volts) and was a bit much for the batteries at 16v per cell, but did not trip on a full charge. This equates to a charge current of 12.5A. minus about .5A through the balance circuit.

I have backed this off to 8kW (53.3%) to try and minimise over voltage on the batteries.